I tried to send money to Revolut account by SWIFT code but fail. It shows “There was a problem eu.validation.failure.swiftcode.swiftCode.unsupported.country”. Does Monzo not support Revolut account?
Your mention of SWIFT makes me think you’re maybe trying to send internationally? I don’t believe that’s possible with Monzo directly, and the advice is to use Transferwise instead.
Does Revolut not offer the option of a GBP balance complete with sortcode and account number? Certainly this is available to UK-based customers, not sure about their product in SG JP US etc
I use “International Transfer” in Monzo app, it offer 2 options to transfer, and I select “SWIFT” 
I chose EUR, but the revolut account was applied in Ireland, not sure is cuz of this…
You can try this method instead: https://www.revolut.com/en-IE/help/adding-money/with-card/how-do-i-add-money-to-my-revolut-account-with-another-card